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PRECAST CONCRETE ELEMENTS122 CPI %u2013 Concrete Plant International %u2013 6 | 2025 www.cpi-worldwide.comIn collaboration with the structural engineer (IMD), a custom fastening system for the hollow core slabs was developed. This system simplifies disassembly and reuse, ensuring that no materials are lost in the process.The components of the temporary courthouse have been stored (see fig. 2) at the building location for the second life. Note the significant amount of storage space required for this purpose. In 2025, these components will be used to construct a new office building (Techbank Enschede NL).Apart from components and products specifically designed for a courthouse, all other elements have also been reused.Design for deconstruction and reassemblyDesigning for reassembly must not compromise structural safety and robustness. Structural coherence, such as the connection between floors and the load-bearing structure, is essential. However, careful consideration should be given to the potential for disassembly and reuse of structural connections.In cases where a precast hollow core slab floor is combined with a steel load-bearing structure, the horizontal diaphragm can alternatively be realized using steel cross-bracing. In this configuration, the floor serves solely as a load-bearing surface, meaning it acts as an enclosure and supports only the directly applied vertical loads.For hollow core slab floors, the horizontal diaphragm is often achieved by applying a structurally reinforced compression layer. However, in a design-for-reassembly approach, this compression layer conflicts with the intended reusability. Instead, horizontal stability can be achieved through a system of tension ties and compression struts or arches. Shear forces can be transferred through the joints, up to a maximum shear stress of 0.15 MPa.Overdimensioning not only enhances structural robustness but also improves reusability. This can be achieved through:%u2022 Larger spans%u2022 Increased floor-to-ceiling height%u2022 Higher design load capacity%u2022 Designing roof slabs to function as intermediate floorsFor connection detailing, simplicity is key. It is important to recognize that additional or specialized connections may increase costs, raise CO2 impact, and reduce reusability %u2013 particularly in the case of hollow core slabs.The more data available on reusable elements, the more accurately their load-bearing capacity can be determined. A material passport can provide insight into the history and raw materials used in a product.Quality assurance for reclaimed construction products still requires further development and is covered in one of the work packages within the ReCreate project.Fig. 2: Storage of the disassembled precast concrete elements.Fig. 3: Reconstruction of the Temporary Courthouse as an office building: state of the reconstruction in summer 2025.Fig. 4: Steel structure with vertical and horizontal stability.